The plate spring is an elongated arc-shaped spring steel with a rectangular cross-section.

The plate spring is an elongated arc-shaped spring steel with a rectangular cross-section. In the most common configuration, the center of the arc provides the position of the axle, while the ring formed at either end is attached to the vehicle chassis. For very heavy vehicles, plate springs can be made from multiple blades stacked together, usually with gradually shortening blades. Plate springs can be used for positioning and a certain degree of damping, as well as spring function. Although interlayer friction provides damping, its control is poor and leads to static friction during suspension motion. For this reason, some manufacturers have started using single piece springs.